<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8"/>
  <title>MacOS</title>
  <style>
    html, body {
      margin: 0;
      height: 100%;
    }

    body {
      width: 100%;
      height: 100%;
      overflow: hidden;
      padding: 10px;
      box-sizing: border-box;
      position: relative;
      /*border: 1px dashed red;*/
    }

    .window-body {
      position: absolute;
      top: 100px;
      left: 100px;
      right: 100px;
      bottom: 100px;
      background: #fff;
      border: 1px solid #acacac;
      box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.3);
      /*box-shadow: inset 0 1px 0 rgba(255, 255, 255, .6), 0 22px 70px 4px rgba(0, 0, 0, 0.56), 0 0 0 1px rgba(0, 0, 0, 0.3);*/
      /*backdrop-filter: saturate(180%) blur(20px);*/
      border-radius: 6px;
      min-width: 400px;
      min-height: 300px;
    }

    .title-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: linear-gradient(to bottom, #ebebeb, #d5d5d5);
      color: #4d494d;
      font-size: 14px;
      text-align: center;
      line-height: 1.6;
      user-select: none;
      border-top: 1px solid #f3f1f3;
      -webkit-app-region: drag;
      border-top-left-radius: 6px;
      border-top-right-radius: 6px;
      border-bottom: 1px solid #b1aeb1;
    }

    .title-bar .title {
      flex: 1;
    }

    .actions {
      min-width: 100px;
      height: 100%;
      display: flex;
      align-items: center;
    }

    .actions button {
      -webkit-app-region: no-drag;
      border-radius: 50%;
      width: 14px;
      height: 14px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      outline: none;
      font-size: 12px;
    }

    .actions button {
      margin-left: 8px;
      position: relative;
    }

    .actions button > span {
      visibility: hidden;
    }

    .actions:hover button > span {
      visibility: visible;
    }

    .btn-red {
      background: #ff5c5c;
      border: 1px solid #e33e41;
    }

    .btn-red:active {
      background: #c14645;
      border: 1px solid #b03537;
    }

    .btn-red > span {
      color: #820005;
      font-weight: bold;
    }

    .btn-red:active > span {
      color: #4e0002;
    }

    .btn-yellow {
      background: #ffbd4c;
      border: 1px solid #e09e3e;
    }

    .btn-yellow:active {
      background: #c08e38;
      border: 1px solid #af7c33;
    }

    .btn-yellow > span {
      color: #9a5518;
    }

    .btn-yellow:active > span {
      color: #5a2607;
    }

    .btn-green {
      background: #00ca56;
      border: 1px solid #14ae46;
    }

    .btn-green:active {
      background: #029740;
      border: 1px solid #128435;
    }

    .btn-green > span {
      color: #006519;
    }

    .btn-green:active > span {
      color: #003107;
    }
  </style>
</head>
<body>

<div class="window-body">
  <div class="title-bar">
    <span class="actions">
      <button class="btn-red"><span>x</span></button>
      <button class="btn-yellow"><span>-</span></button>
      <button class="btn-green"><span>+</span></button>
    </span>
    <span class="title">Window</span>
    <span class="actions"></span>
  </div>
</div>

</body>
</html>
